煤低温氧化热解的热分析实验研究

在热分析动力学的基础上,对阳泉煤样运用同步热分析仪进行150℃下的氧化以及热解实验,得出该煤样相应的TG-DSC曲线。通过两者的TG-DSC曲线,对比分析煤样的热量释放情况,并结合曲线设定多项式形式的机理函数以分析其动力学特性。实验研究得出:该煤的低温氧化过程较之热解过程是个明显的氧化放热过程;该煤低温氧化和热解过程的最佳机理函数都为多项式,并且相应过程中的TG曲线和DSC曲线适用于同一个机理函数,这与一般所定义的机理函数不同;热解过程较之氧化过程所需的表观活化能较大,相同条件下较易发生煤的氧化自燃。

Thermal Analysis Experiment on Low-temperature Oxidation and Pyrolysis of Coal

Based on thermal analysis kinetics,the simultaneous thermal analyzer was used to conduct an experiment of 150℃ oxidation and pyrolysis of Yangquan coal,and the corresponding TG-DSC curves of coal samples were obtained. Through the TG-DSC curves,the heat release of coal sample was comparatively analyzed,and its dynamic characteristics were analyzed through the mechanism function of polynomial form that was defined on the basis of the curves. Experimental results show that the low-temperature oxidation process of coal,contrasted with the pyrolysis process,is a clear exothermic oxidation process;the best mechanism functions of low-temperature oxidation and pyrolysis process of coal are all polynomial,and the TG curve and DSC curve in their corresponding process are applicable to the same mechanism function,which is different from the general mechanism function. The apparent activation energy needed in the pyrolysis process is larger than that needed in oxidation process,the spontaneous combustion of coal oxidation is more easier to happen under the same condition.